She wasn't necessarily having trouble. It was just another superfluous spell that she was experimenting with, and Pinkie inadvertently directed that spell towards a bunch of random objects. Pinkie basically killed a frog and a bird by throwing of Twilight's aim.

did any-pony notice that when they were singing the song for starting the festival she was levitating the book and her horn was glowing with magic in one scene....
Thats right Hasbro, I noticed you ****** up.

You know you can say anybody, instead of "any-pony." Frankly I don't see what the point of that is. I would have known what you would have meant if you said anybody. Seems to me like that's the kind of thing that everybody is doing because everybody else is doing it.